Safe and reliable operation of a railroad system may be dependent upon the integrity of the rolling mechanisms of the vehicles travelling over the rails. Worn or damaged train wheel bearings may increase the rolling friction of the axle thereby increasing the power required to pull the train. In addition, worn, damaged or defective bearings may cause excessive wear to the train axle and, in the case of failure of the bearing, may even cause the axle to lock up, preventing rotation of the wheel and thus resulting in a potential fire hazard due to the heat buildup and potential sparking caused by friction of the locked wheel scraping along the rail. A locked up bearing will eventually burn off and possibly cause a derailment of the train.
Bearing temperatures may be determined by sensing a temperature of the wheel bearing indirectly through a bearing box surrounding the wheel bearing on a rail car of a train. In current railway systems, train inspection stations may be installed adjacent to the tracks approximately every 15-25 miles along the train line. Infrared radiation (IR) thermal imaging sensors are mounted at the train inspection stations, defect detector stations and/or hot bearing detector stations. The sensors are aimed toward the tracks to detect IR energy emitted by the wheel bearings and the wheels of passing rail cars. The IR energy may be indicative of the temperatures of the wheel bearings and the wheels. If the IR energy indicates that the temperatures of the bearings or the wheels is above a threshold where the safety and performance of the train undercarriage components may be compromised, the train inspection station may transmit warning messages to the train or to a back office responsible for the trains and/or the train line to provide an alert of the potentially hazardous situation.